Assessment of textile dye remediation using biotic and abiotic agents

The aim of the current work was to assess the removal of direct and reactive dyes using biotic and abiotic agents. Removal of dyes and their derivatives from aqueous solutions was investigated using sugarcane bagasse, sawdust, rice straw, charcoal and fungal biomass as dye removing agents. Seven fungal strains known to have high capacity in removing textile dyes were used. Results of this study indicated that Penicillium commune, P. freii, and P. allii removed 96, 64 and 65%, respectively, of direct violet dye after two hours of incubation. In addition, the use of rice straw was shown to be more efficient in dye removal, than was bagasse or sawdust. Rice straw was effective in removing 72% of direct violet dye within 24 hours. However, with reactive dyes, removal activity was reduced to 27%. Similar trends were recorded with the other tested biotic agents, fast removal of reactive dye was not found after 48 hours of contact time. Results of this study indicate that low-cost, renewable, bioadsorption agents are relatively effective in removing textile dyes from solution.     

Role of white rot fungus Funalia trogii in detoxification of textile dyes

Toxic and genotoxic effects of the textile dyes on organisms suggest the need for remediation of dyes before discharging them into the environment. For this reason, the ability of Funalia trogii pellets to detoxify textile dyes was investigated and evaluated. Although, textile dyes are toxic substances for many microorganisms, the pellets were able to decolorize and detoxify the azo dyes used. Astrazon Blue and Red dyes inhibit growth of F. trogii and S. aureus on solid medium in a concentration dependent manner. The toxicity of these dyes on a fungus, F. trogii and a bacterium, S. aureus was significantly decreased after pretreatment with fungal pellets.     

Microflora involved in textile dye waste removal

Textile dyes are heavily used in factories for coloring different cloth materials. This work was designed to identify microorganisms capable of removing textile dyes, either by biodegradation or by biosorption. We expected to isolate microorganisms adapted to high dye concentrations from sites near textile industry complex. An experiment was conducted to study the efficiency of the isolates in removing textile dyes. The tested dyes were used as carbon and nitrogen sources for isolation of soil and/or water microorganisms capable of removing textile dyes wastes from factories effluent. The results indicated the low efficiency of both bacteria and actinomycetes in clean-up the effluent from the waste dyes in 10-21 days. On the other hand six fungal isolates were obtained by plating factory effluent on Martin's medium and media containing dyes as the sole source of carbon and nitrogen for growth. These isolates fell in two genera, Aspergillus and Trichoderma. Results of these studies revealed the potential capacity of these fungi to decolorize the tested dyes in comparatively short time (2-24 hours) indicating strong efficiency of dye bioremediation by the fungal isolates. Since the process involved is mostly fast interaction between the fungal mycelium and the dye in the media, the possible mechanism could be based on a biosorption of such chemicals on the intact fungal biomass, rather than direct biodegradation of the compounds.     

Enhancing bioremoval of textile dyes by eight fungal strains from media supplemented with gelatine wastes and sucrose

Eight Aspergillus strains were found to be successful in removing textile dyes from liquid media. These fungal strains were grown on medium containing: gelatine wastes and sucrose, as sources of nitrogen and carbon to test the possible speed up of the dyes removing while fungus biomass is building up in the media. The growth of fungal strains ranged from 10 to 110 mg biomass dry weight/100 ml medium. This growth induced high decolorization percentages, which ranged 33-95% within eight days. Two textile dyes Direct brown and Polar red were included in the study. The growth of the fungal strains as well as decolorization percentage of the dyes increased after 5, 6, and 8 days from incubation time with most tested strains. With Direct brown dye the strains number 2, 5, 31 and 37 recorded the highest percentage of decolorization (91, 92, 93 and 95 respectively) after incubation for 6 days. Fungal strains Aspergillus 5 and 31 gave the highest mycelium dry weight being 110 mg. Most of fungal strains induced 86 to 95 percentage of decolorization after 6 days incubation with Polar red dye. The possible toxicity of the remaining supernatant media after fungal biomass removal was tested by Ames test to assess the residual mutagenic agents remaining after dye removal, using three strains of Salmonella typhimurium (TA 1535, TA 1537, TA 1538). The results showed that the toxicity of the dyes, measured by Ames test could be removed by the dye absorption on the fungal biomass.     

Relationship of chemical structures of textile dyes on the pre-adaptation medium and the potentialities of their biodegradation by Phanerochaete chrysosporium

Azo dye derivatives of azobenzene constitute the largest group of dyes used in the textile industry and possess recalcitrant chemical groups, such as those of azo and sulphonic acid. Some microorganisms are able to degrade these aromatic compounds. In the present work, decolourisation of culture media containing azo dyes by the ligninolytic fungus Phanerochaete chrysosporium was achieved under nitrogen-limited conditions. The dyes used in the study are derivatives of meta- or para-aminosulphonic or aminobenzoic acids and include in their structures groups such as guaiacol or syringol, which are bioaccessible to the lignin degrading fungus P. chrysosporium. The aim of this study was to pre-adapt the microorganism to the structure of the dyes and to establish the relationships of the chemical structure of the dye present in the pre-adaptation medium with the chemical structure of the dye to be degraded. The azo dye used in the pre-adaptation medium that gave the best overall decolourisation performance was a meta-aminosulphonic acid and guaiacol derivative. The azo dye derivative of a meta-aminobenzoic acid and syringol showed a better performance in the decolourisation assays. Preliminary GC-MS studies indicated the formation of a nitroso substituted catechol metabolite, a precursor of aromatic ring cleavage, which was confirmed to occur by an enzymatic assay. The presence of this type of metabolite allows the establishment of a possible metabolic pathway towards mineralisation.     

Genotoxicity of degradation products of textile dyes evaluated with rec-assay after PhotoFenton and ligninase treatment.

Fourteen textile and biological dyes, belonging to the azo, triphenylmethane, anthraquinone, heterocyclic, oxazine, and methine/polymethine groups, were degraded using the PhotoFenton treatment (PFT) and the Phanerochaete chrysosporium crude ligninase enzyme (ED) treatment. The genotoxicity of the dyes and of their degradation products were assessed with the rec-assay. We found that the genotoxicity depended on the dye and on the method of degradation. In general, PFT was better than ED in decreasing the genotoxicity. Basic dyes showed complete or maximum loss of genotoxicity, whereas the vat group was more resistant. The azo group showed varied results. Crystal Violet was the only dye whose genotoxicity increased after PFT. Our results suggest that PFT and ED are two effective treatment methods to reduce the genotoxicity of dyes in waste waters.     

Astrazon Red dye decolorization by growing cells and pellets of Funalia trogii

The dye decolorization activity of fungal pellets has been compared with another method based on the decolorization of dye by growing cells. The pellet method was more advantageous than the growing cell method. The growing cells of F. trogii decolorized 21% of the dye in distilled water medium and 16% in stock basal medium in 24 h. On the other hand, Funalia trogii pellets rapidly decolorized the Astrazon Red dye, mono-azo textile dye, in 24 h, without any visual sorption of any dye to the pellets. The effect of various supplements on longevity of decolorization by free pellets was also tested. Glucose and cheese whey supplementation improved dye decolorization performance of the pellets and remained high and stable for 10 days. We also tested the dye decolorization ability of pellets immobilized on activated carbon. These pellets showed the stable dye decolorization activity during the repeated batch experiments. The study revealed that dye decolorization by pellets is more effective method than the growing cell method.     

Decolorization of diazo-dye Reactive Blue 172 by Pseudomonas aeruginosa NBAR12

A novel bacterial strain capable of decolorizing textile dyes was isolated from dye contaminated soil obtained from industrial estate of Ahmedabad, Gujarat, India. The bacterial isolate Pseudomonas aeruginosa NBAR12 was capable of decolorizing 12 different dyes tested with decolorization efficiency varying in the range of 80 to 95%. Maximum extent as well as rate of Reactive Blue 172 (RB 172) decolorization was observed when glucose (2 g x l(-1)) and yeast extract (2.5 g x l(-1)) were supplemented in the medium. The optimum dye pH and temperature for dye decolorization was found to be 7 and 40 degrees C, respectively. The decolorizing activity was found to increase with increasing the dye concentration from 50 to 400 mg x l(-1). The dye decolorization was strongly inhibited at 500 mg dye l(-1) in the medium. High performance thin layer chromatography analysis indicated that dye decolorization occurred due to the breakdown of dye molecules into colorless end products.     

Evaluation of biotoxicity of textile dyes using two bioassays

The toxicity of eight textile dyes was evaluated using two bioassays namely: Ames test and seed germination test. The Ames test is widely used for the evaluation of hazardous mutagenic effect of different chemicals, as a short-term screening test for environmental impact assessment. The eight-textile dyes and Eithidium bromide dye (as positive control) were tested with five "his" Salmonella typhimurium strains: TA 100; TA 98; TA 1535; TA 1537; TA 1538. Using six concentrations of each dye (2.5 microg/ml, 4.5 microg/ml, 9 microg/ml, 13.5 microg/ml, 18 microg/ml, and 22.5 microg/ml) revealed that, most of the dyes were mutagenic for the test strains used in this study. The high concentrations of dye eliminated microbial colonies due to the high frequency of mutation causing lethal effect on the cells.In this work the phytotoxicity of different soluble textile dyes was estimated by measuring the relative changes in seed germination of four plants: clover, wheat, tomato and lettuce. The changes in shooting percentages and root length as affected by dye were also measured. Seed germination percent and shoot growth as well as root length were recorded after 6 days of exposure to different concentrations of textile dyes in irrigation water. The results show that high concentrations of dyes were more toxic to seed germination as compared with the lower concentrations. However, the low concentrations of the tested dyes adversely affected the shooting percent significantly.     

Decolourisation of diverse industrial dyes by some Phlebia spp. and their comparison with Phanerochaete chrysosporium

Three species of Phlebia, viz. P. brevispora, P. fascicularia and P. floridensis have been evaluated for their potential to decolourise eight industrial dyes including; reactive yellow, reactive orange, reactive red, rathidol scarlet, coracryl black, coracryl pink, coracryl violet and coracryl red. The cultures used for the present study were pre adapted by growing these on yeast glucose agar medium supplemented with Poly-R 478, a reference dye. The fungal cultures were grown in mineral salts broth and harvested after different incubation periods to obtain their cell free enzyme extracts which were then used to assess their ability to decolourise the above mentioned dyes. The extracts obtained from the cultures grown for six days significantly decolourised the tested dyes. The study revealed Phlebia spp. to be better dye decolourisers than Phanerochaete chrysosporium.     

Screening of filamentous fungi for the decolorization of a commercial reactive dye

The aim of this work is to verify the ability of 19 isolates of 13 different fungal species to decolorize the reactive dye blue‐BF‐R. The isolates of Pleurotus pulmonarius, P. ostreatus, P. ëous, P. citrinopileatus, Lentinus edodes, Phanerochaete chrysosporium, Schizophyllum commune, Agaricus blazei, Ganoderma sp. and four isolates obtained from textile effluent were evaluated in minimum liquid medium. In addition, seven of them were also evaluated on solid medium, and both media were both added 0.5 g dye/l. All isolates evaluated on solid medium decolorized the dye. The isolates Phanerochaete chrysosporium CCB478 and Lentinus edodes CCB047 were the ones that presented the fastest and slowest growth, respectively. Despite the isolate of the textile effluent had grown on solid medium, it did not decolorize the dye. All the isolates of the genus Pleurotus, except the isolate Pleurotus ëous CCB440, decolorized the dye in liquid medium. They presented decolorization percentage ranging from 39% to 51%. The absorbance ratio (Abs₅₉₀/Abs₄₅₅) of the culture medium inoculated with these isolates decreased throughout the experiment indicating the fungal dye degradation. The others presented decolorization percent below 8%. The isolates of Pleurotus, except the isolate Pleurotus ëous CCB440, were able to decolorize and to degrade the commercial reactive dye blue‐BF‐R. The results indicate their potential to be used in the treatment of effluents containing this dye. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Production of laccase from Pleurotus florida using agro‐wastes and efficient decolorization of Reactive blue 198

Pleurotus florida NCIM 1243 produced laccase as the dominant lignolytic enzyme during the dye decolorization. Banana peel was the best substrate for extracellular laccase production under solid state fermentation when compared to mandarin peel and cantaloupe peel. The maximum activity of laccase (5.4 U/g) was detected on the 10 day. The ratio of banana peel: mandarin peel: cantaloupe peel (5:2:3) showed increased production of laccase (6.8 U/g). P. florida produced two extracellular laccase isoenzymes (L1 and L2). The half life of laccase at 60 °C was 2 h and at 4 h it retained 25% residual activity. P. florida laccase showed high thermostability and an interesting difference was noticed in the behavior of laccase isoenzymes at different temperature. The L1 isoenzyme of laccase showed remarked thermostability at 60 °C in the native PAGE when compared to L2 isoenzyme. The optimum pH, temperature and enzyme concentration for maximum decolorization was found to be 4.5, 60 °C and 1.2 U/ml, respectively. Partially purified laccase enzyme showed excellent decolorization activity to Reactive blue 198. The maximum decolorization (96%) was observed at lower dye concentrations (50–100 ppm) which decreased markedly when the dye concentration was increased beyond 150 ppm. The thermostable laccase of P. florida could be effectively used to decolorize the synthetic dyes in the textile effluent and other biotechnological applications. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Flow cytometric analysis using live/dead staining for yeast cells which were autoclaved and treated with various disinfectants

Flow cytometric analysis using live/dead staining dyes was applied to discriminate yeast cells treated with autoclave and various disinfectants. One fluorogenic dye, propidium iodide cannot leak into live cells with intact membranes, whereas another fluorogenic dye, thiazole orange is permeant and can enter all cells, live and dead. Thus a combination of these two dyes can classify cell populations into live, injured and dead cells. When the yeast cells were autoclaved at 121 degrees C for 5 min, almost all the cells were classified as being dead, but some yeast strains contained a little injured cells (up to 8.5%). It was also demonstrated that none of the yeast cells autoclaved could produce a visible colony on the agar plate. The 70% ethylalcohol was the most effective disinfectant tested. Almost all the yeast cells treated were classified as being dead, and no visible colony appeared after agar plate incubation. The cell suspensions of yeast treated with 0.5% chlorhexidine contained injured cells with >95%, but no visible colony appeared. Whereas, the numbers of live yeast cells after treatment with 0.025% benzalkonium chloride were less than detectable counts (<1.0%) by flow cytometry, however, visible colonies appeared on the agar plate with 10(1) to 3.6 x 10(3) colony forming units/ml. With these results, it became apparent that the combination with fluorogenic dyes and flow cytometry can provide a reliable test method to discriminate dead and/or injured cells from the reproductive live yeast cells, and is applicable for further studies. However, it should be noted that minimum detectable levels are sometimes far different between the standard colony forming assay and the flow cytometric determination.     

Decolorization of synthetic dyes by the deuteromycete Pestalotiopsis guepinii CLPS no. 786 strain

The ability of Pestalotiopsis guepinii CLPS no. 786 to decolorize 13 dyes of varied structure was analyzed and compared with that of the basidiomycete Phanerochaete chrysosporium . Nine dyes representing anthrapyridone, azo, N-heterocyclic and triphenylmethane chromophores, but none with the O-heterocyclic group, were decolorized by P. guepinii when added to an agar medium. Studies with liquid cultures revealed that P. guepinii transformed both crystal violet and methylene blue B dyes, and adsorbed different chromophores onto its mycelium.     

Contact dermatitis due to para-phenylenediamine (PPD) on a temporal tattoo with henna. Cross reaction to azoic dyes

Henna is used as a hair dye and to make temporary tattoos on the skin. It is usually mixed with p-phenylendiamine (PPD) to increase colour intensity and to reduce the time of fixation on the skin proteins. PPD can cross react with azoic dyes which are used as textile dyes. We studied a patient with skin eczema in the area of a henna temporary tattoo. The epicutaneous tests performed with the standard Trolab and Chemotecnique hair dressing and textile batteries, showed positive results to PPD, p-toluendiamine, 5-4aminophenol, Yellow 3, Orange Red and Red 1, and negative results to three types of henna. The eczema in this patient was due to sensitisation to PPD on a henna tattoo with cross reaction to azoic dyes. The recent fashion of applying temporal tattoos in occidental countries may produce an increase in the frequency of contact dermatitis due to henna mixtures with cross- reaction to related compounds and possibly producing permanent skin changes.     

Rhamnolipid from Pseudomonas desmolyticum NCIM-2112 and its role in the degradation of Brown 3REL

The biosurfactant produced by Pseudomonas desmolyticum NCIM 2112 (Pd 2112) was confirmed as rhamnolipid based on the formation of dark blue halos around the colonies in CTAB-methylene blue agar plates and the content of rhamnose sugar. The average yield of rhamnolipid was 0.398 g/l/day when grown on hexadecane as sole carbon source. Pd 2112 emulsification potential associated with cell free culture broth was stable for 72 h using various hydrocarbons and vegetable oils. Chemical structure of the biosurfactant was identified as mono-rhamnolipid (Rha-C(6) -C(8) ) using HPTLC, fourier transform infrared spectroscopy, (1) H and (13) C NMR and gas chromatography-mass spectroscopy analysis. Pd 2112 mono-rhamnolipid (1 mg/ml) had increased permeabilization of Bacillus sp VUS NCIM 5342 and increased decolorization rate of textile dye Brown 3REL by 50%. Extracellular activities of lignin peroxidase and veratryl alcohol oxidase, enzymes involved in dye degradation, were significantly increased in the presence of mono-rhamnolipid by 324.52% and 100% respectively. Scanning electron micro-scopy observations revealed that rhamnolipid did not exert any disruptive action on Bacillus cells as compared to Tween 80. The mono-rhamnolipid of Pd 2112 has potential for its application in biodegradation of textile dyes.     

Occupational Asthma Induced by the Reactive Dye Synozol Red-K 3BS

Various reactive dyes can elicit occupational asthma in exposed textile industry workers. To date, there has been no report of occupational asthma caused by the red dye Synozol Red-K 3BS (Red-K). Here, we report a 38-year-old male textile worker with occupational asthma and rhinitis induced by inhalation of Red-K. He showed positive responses to Red-K extract on skin-prick testing and serum specific IgE antibodies to Red-K-human serum albumin conjugate were detected using an enzyme-linked immunosorbent assay. A bronchoprovocation test with Red-K extract resulted in significant bronchoconstriction. These findings suggest that the inhalation of the reactive dye Red-K can induce IgE-mediated occupational asthma and rhinitis in exposed workers.     

Amine reactive dyes: an effective tool to discriminate live and dead cells in polychromatic flow cytometry

Membrane-damaged cells caused by either mechanical trauma or through normal biological processes can produce artifacts in immunophenotyping analysis by flow cytometry. Dead cells can nonspecifically bind monoclonal antibody conjugates, potentially leading to erroneous conclusions, particularly when cell frequencies are low. To date, DNA intercalating dyes (Ethidium monoazaide (EMA), Propidium Iodide, 7AAD, etc.) or Annexin V have been commonly used to exclude dead cells; however, each suffer from technical problems. The first issue with such dyes is the dependence on a consistent dead cell source for fluorescence compensation. Another major issue is the stability of the staining; except for EMA, fixation and permeablization used for intracellular staining procedures can cause loss of fluorescence. EMA requires a UV exposure to covalently bond to DNA; while this dye is effective and is not affected by intracellular treatments it is weakly fluorescent. Here we report on the optimization of a new class of viability dyes, the amine reactive viability dyes (ViD) as a dead cell exclusion marker. The inclusion of ViD into the staining panel was found to be simple, reproducible and can have a significant benefit on the accuracy of identifying appropriate cell populations. We show the fluorescence of cells stained with these dyes correlates with traditional dead cell discriminating markers, even after fixation and permeabilization. Amine reactive viability dyes are a powerful tool for fluorescence immunophenotyping experiments.     

Reduction in the mutagenicity of synthetic dyes by successive treatment with activated sludge and the ligninolytic fungus, Irpex lacteus

Synthetic dyes are released in wastewater from textile manufacturing plants, and many of these dyes are genotoxic. In the present study, the mutagenicity of azo, anthraquinone, and triphenyl methane dyes was investigated before and after successive biodegradation with activated sludge and the ligninolytic fungus, Irpex lacteus. Two biodegradation systems were used to reduce the genotoxicity of dyes that were not efficiently inactivated by activated sludge alone. Mutagenicity was monitored with the Salmonella reversion assay conducted with the base-pair substitution detector strains, TA100 and YG1042, and the frame-shift detector strains, TA98 and YG1041, with and without rat liver S9. All dyes except for Congo Red (CR) were mutagenic with S9 activation. Assays conducted with the dyes indicated that only the azo dye Reactive Orange 16 (RO16) was mutagenic in both TA98 and TA100. Methyl Red and Disperse Blue 3 (DB3) were mutagenic in TA98, YG1041 and YG1042, while Reactive Black 5 was mutagenic in YG1041 and YG1042. Remazol Brilliant Blue R (RBBR), Crystal violet (CV) and Bromophenol Blue (BPB) were mutagenic only in TA98, but the toxicity of the latter two dyes complicated the evaluation of their mutagenicity. CR was not mutagenic in any of the tester strains. Biodegradation studies conducted with RO16 and DB3 indicated that the two-step biodegradation process reduced the mutagenic potential of RO16 and DB3 to a greater extent than activated sludge alone; the mutagenicity of the two dyes was reduced by 95.2% and 77.8%, respectively, by the two-step process. These data indicate that the combined biodegradation process may be useful for reducing the mutagenicity associated with wastewater from textile factories that contain recalcitrant dyes.     

Renal test dyes III

Summary The effects of the triaryl-methane dyes Lissamine Green SF (LF SF). Lissamine Green BN (LG BN), Lissamine Green V (LG V) and Kiton Pure Blue V (KPB V) on renal functions of rats and on sodium transport across isolated frog skin have been investigated.The experiments failed to show any natriuretic or diuretic effects of the purified dyes on the rat kidney. In the continuous infusion experiments, which lasted 3 1/2 h, the amount of the dye infused was equivalent to a passage time measurement every 3 min. In rapid injection experiments LGV was injected every 5 min for 1 h. The dyes did not have any effect on inulin clearance either. Previously reported effects of the dyes can be partly explained by the presence of sodium sulfate in commercially available dyes. Experiments with LG V showed that the dye also has no effect on the potential difference or short circuit current across the isolated frog skin. This supports their usefulness as renal test dyes.Supported by Deutsche Forschungsgemeinschaft (SFB 90)